I am trying to use an Analog to digital converter to read a voltage, then save that voltage to an SD card. Should be pretty simple right? Both components are connected to my Arduino Fio on the same SPI bus. I know my wiring is okay and my code will work for a while. But eventually, something goes wrong and I begin receiving only all 0's or all 1's from my ADC when I should be getting a different voltage reading. If I change the voltage being sent to my ADC, I still receive the same incorrect values of all 0's or all 1's.